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111.
Gully erosion is commonly associated with agricultural landscapes where vegetation clearance and farming practices increase runoff, leading to fluvial incision. However, gully erosion can also occur in forests that have undergone some form of disturbance, either natural or resulting from human impacts. This paper reports on recent gully development within areas of undisturbed indigenous forest as a result of a high magnitude rainfall event on the East Coast of New Zealand's North Island. This region, through a combination of crushed and sheared rock types, steep topography, and tectonic and climatic setting, has high natural rates of erosion, exacerbated by European deforestation in the late 19th and early 20th centuries.Sequential air photographs, spanning a 58 year period between 1939 and 1997 were used to classify and document the growth and recovery of gully systems in the 14.1 km2 headwaters of the Mangaoporo catchment. Following a severe cyclone in 1988, with a rainfall of 535 mm, there were 21 active gully systems within the indigenous forest. On photography prior to 1988 only four gully systems were present. During this period there were 8 major rainfall events (150–250 mm). Despite further 5 rainfall events of 150–250 mm between 1988 and 1997 all gully systems showed signs of recovery, with a combined reduction in active area of 37%. The nature and location of these features is strongly influenced by lithology (orientation of jointing and bedding), and to a topographic threshold defined by catchment slope and catchment area.  相似文献   
112.
Water relations of four tree species were studied in four sites in the drylands of northern Ethiopia. Predawn water potentials were significantly higher at all sites as compared to midday measurements for Acacia etbaica and Boswellia papyrifera. In contrast, Lannea fruticosa revealed this significant difference only once, while Terminalia brownii at only two of the four sites. An analysis of variance showed that A. etbaica has a wider tolerance range as compared to the other species. There was no significant difference among the four sites in terms of predawn, midday and diurnal ranges of water potential. The study revealed that A. etbaica and B. papyrifera are performing better as compared to T. brownii and L. fruticosa under the current climatic conditions. Understanding the physiological basis of survival, productivity, ability to cope with low moisture availability, and growth potential of indigenous species in the drylands is essential for the utilization and promotion of these and other species.  相似文献   
113.
The 2001 census count of Indigenous Australians produced an intercensal change in numbers that cannot be explained by demographic processes alone. Using census and vital registration data, this paper unravels the components of such change and provides new insight into Indigenous population dynamics. In particular, it establishes the first estimates of proximate determinants of fertility, and extends mortality analysis by examining the components of low Indigenous life expectancy. Results show that demographic factors account for only 69 per cent of population change. Of these components, national Indigenous fertility is found to be below replacement level, while lack of convergence between Indigenous and non-Indigenous mortality remains. As Indigenous socio-economic circumstances are spatially diverse, the paper also explores the geography of demographic processes using data for 36 ATSIC regions and capital city/balance of State classifications. This reveals continued high fertility across parts of north Australia and an indication that mortality levels are associated with degree of urban residence.  相似文献   
114.
Population estimates are rarely constructed for ecological regions. The recent establishment of a Desert Knowledge Cooperative Research Centre (CRC) generates a need for such estimates. This paper obliges by presenting Indigenous and total population projections for the Australian desert to 2016. The desert is found to be a region of relatively low population growth in national terms, contrary to the experience of many other parts of non-metropolitan Australia where population decline is prevalent. Also noted is the markedly different growth observed for the Indigenous and non-Indigenous components of the desert population, with the former projected to increase much more rapidly over time. It is likely that virtually all of the increase in the desert population over the next 15 years will arise from natural increase among Indigenous peoples. As a consequence, the Indigenous share of the regional population is projected to rise from 20 per cent in 2001 to 24 per cent by 2016, with attendant consequences for social and economic policy.  相似文献   
115.
Involvement in scientifically structured habitat monitoring is a relatively new concept to the peoples of Torres Strait. The approach we used was to focus on awareness, and to build the capacity of groups to participate using Seagrass-Watch as the vehicle to provide education and training in monitoring marine ecosystems. The project successfully delivered quality scientifically rigorous baseline information on the seasonality of seagrasses in the Torres Strait—a first for this region.  相似文献   
116.
Canada is in a liminal space, with renewed struggles for and commitments to indigenous land and food sovereignty on one hand, and growing capital interest in land governance and agriculture on the other. While neoliberal capital increasingly accumulates land-based control, settler-farming communities still manage much of Canada’s arable land. This research draws on studies of settler colonialism, racial hierarchy and othering to connect the ideological with the material forces of settler colonialism and show how material dominance is maintained through colonial logics and racially ordered narratives. Through in-depth interviews, I investigate how white settler farmers perceive and construct two distinctly ‘othered’ groups: Indigenous peoples and migrant farmers and farm workers. Further, I show the disparate role of land and labour in constructing each group, and specifically, the cultural and material benefits of these constructions for land-based settler populations. At the same time, settler colonial structures and logics remain reciprocally coupled to political conditions. For instance, contemporary neoliberalism in Canadian agriculture modifies settler colonial structures to be sure. I argue, however, that political economic analyses of land and food production in Canada (such as corporate concentration, land grabbing and farm consolidation) ought to better integrate the systemic forces of settler colonialism that have conditioned land access in the first place. Of course, determining who is able to access land—and thus, who is able to grow food—continues to be a territorial struggle. Thus, in order to shift these conditions we ought to examine how those with access and control have acquired and maintained it.  相似文献   
117.
Using the Canadian Arctic as a case study this paper explores how Internet-based research can be used to advance area studies in an era of rapid global change. Regions of the world are rapidly changing due to social, technological, and environmental processes, and traditionally marginalized groups are increasingly using digital tools to help shape new geographical imaginations of these regions. Digital research is uniquely capable of analyzing these political uses of digital technologies, to produce a better understanding of how many different stakeholders are shaping emerging geographical imaginations. The Canadian Arctic offers a particularly powerful case study to understand these processes both because it represents a geographic region that is complex, multi-scalar, and rapidly evolving, and also because it is a region in which traditionally marginalized indigenous groups are using the Internet to increase the visibility of their perspectives. This paper develops an innovative methodology, combining computational analysis of ‘big data’ along with traditional forms of qualitative analysis, to analyze representations of the Arctic across the websites of five different organizations. These organizational websites were chosen because each of the organizations has a different relationship to the Arctic, operates at a different geographic scale, has some relevance to areas of the Canadian Arctic in which Inuit live, and has a large website. The analysis successfully reveals how these different organizations use the web to shape different types of geographic imaginations of the Arctic, as well as the types of discursive politics being used by the organizations to push forward their own political goals. The result is a powerful form of area studies capable of highlighting the geographic imaginations and re-imaginations of a complex set of actors operating at many different scales.  相似文献   
118.
The commodification of traditional knowledge is a lively topic for academic debate, with opinions ranging from categorical rejection of this process, to views that it could be a liberating act. This debate is often characterised by generalisations and a lack of empirical engagement. This paper presents a case study of the commercialisation of traditional medicinal knowledge of the San in Southern Africa. A scenario survey in 3 communities reveals a range of different views amongst individuals and communities, much of which could be linked to differing local and historic socio-economic factors. Although the survey indicates that commodification is widely accepted, the subsequent use of a ‘life story’ approach to examine the actual commercialisation of the Hoodia (Hoodia Gordonii—a plant with appetite suppressant properties), shows that this acceptance is problematic. San informants reflect on it as a pragmatic choice informed by experiences of deprivation and economic hardship, resulting in a process which changes the cultural meaning of the plant and undermine its traditional healing power for the San themselves.  相似文献   
119.
For Aboriginal and Torres Strait Islander (Indigenous) Australians, the wellbeing of the community in which one lives and/or has an ongoing attachment to is an important aspect of individual health and wellbeing. In non-Indigenous policy discourse, the main way to summarise community-level wellbeing is through indices of socioeconomic outcomes that can be used to rank regions or areas within regions. While these have been produced for the Indigenous population, they only capture one particular aspect of community wellbeing. The analysis presented in this paper extends our knowledge of place-based community wellbeing by looking at the presence or absence of particular facilities, barriers to accessing services, and neighbourhood or community problems. Indigenous Australians in remote areas were less likely to report the presence of a number of facilities and more likely to report barriers to accessing government services. However, there were no consistent differences in the reporting of neighbourhood and community problems—some types of problems had a higher incidence in non-remote areas (e.g. theft and dangerous or noisy driving), whilst other problems were higher in remote areas (alcohol, illegal drugs and violence). Indices of these variables were also found to be associated with individual emotional wellbeing, providing prima facie evidence of the link between community and individual measures.  相似文献   
120.
Aboriginal inhabitants of the Wet Tropics of Queensland advocate for greater inclusion of their Indigenous knowledge (IK) in natural resource management (NRM) to fulfil their customary obligations to country and to exert their Native Title rights. Despite a legal and institutional framework for inclusion of IK in NRM, IK has so far been applied only sporadically. We conducted an ethnographic case study to investigate perceptions on IK, science and how they affect integration of the two knowledge systems in the Wet Tropics. Our results show that IK and science are perceived as different concepts; that integration is limited by weak Indigenous internal and external governance; and that stronger Aboriginal governance and more focused engagement strategies are required to further the application of IK in local NRM. We conclude by arguing that NRM in the Wet Tropics needs to be reconceptualised to accommodate IK holistically, by considering its epistemology and the values and ethic that underpin it.  相似文献   
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